# From the abstract:

# > We argue that the best estimate of the effects of campaign contact and advertising on Americans’ candidates choices in general elections is zero. First, a systematic meta-analysis of 40 field experiments estimates an average effect of zero in general elections. Second, we present nine original field experiments that increase the statistical evidence in the literature about the persuasive effects of personal contact tenfold. These experiments’ average effect is also zero. In both existing and our original experiments, persuasive effects only appear to emerge in two rare circumstances. First, when candidates take unusually unpopular positions and campaigns invest unusually heavily in identifying persuadable voters. Second, when campaigns contact voters long before election day and measure effects immediately—although this early persuasion decays.

# The authors focus on overall effect.

# Subset treated long before election is less substantively important because the authors claim explicitly that the effect decays. Including those in the overall effect will make the effect look bigger and the studies look better powered.

# Subset on unusual candidates and heavy investment via cross-pressure looks like a qualitative description of very few studies in the article.

# For these reasons, we only consider the overall estimate.

source(here::here("code/load.R"))

here("data/meta_analyses_raw/KalBro2017/data/merged_data.csv") |>
    read_csv() |>
    mutate(meta_id = "KalBro2017",
           subfield = "AP",
           question = "What is the effect of campaign contact and advertising on vote choice in US elections?",
           study_year = gsub(".*(\\d{4}).*", "\\1", Experiment.for.Clustering),
           study_year = as.numeric(study_year)) |>
    select(meta_id,
           subfield,
           question,
           study_id = Experiment.for.Clustering,
           study_year,
           estimate = CACE,
           std.error = SE) |>
    write_csv(here("data/meta_analyses_clean/KalBro2017.csv"))
